Breech mechanisms



Jan. 29, 1957 A. D. wlLLHAUcK 2,779,242

BREECH MECHANI'SMS Filed April 4, 1952 6 ShetS-Sheet l Jan. 29, 1957 A. D, WILLHAUCK 2,779,242

BREECH MECHANISMS Filed April 4, 1952 6 Sheets-Sheet 2 f il \1-. N E Nw *f5 m 4 OQ@ Nm) N S3 Q \Q @s 1S N Inventor 0a X Q 1 Augustusl) /VZZ/zauc/f l [By /zz'SAzzOrg Jan. 29, 1957 A. D. WILLHAUCK BREECH MECHANISMS 6 Sheets-Sheet 3 Filed April 4, 1952 i I l l I 1 IJ A. D. WILLHAUCK Jan. 29, 1957 BREECH MECHANISMS 6 Sheets-Sheet 4 Filed April 4, 1952 formez] Jan. 29, 1957 A. D. wlLLHAUcK 779,242

BREECH MECHANISMS Filed Aprily 4, 1952 s sheets-sheet 5 Jan. 29, 1957 A. D. wlLLHAUcK 2,779,242

BREx-:CH MEcHANrsMs Filed April 4, 1952 e sheets-sheet e 2,779,242 BREECH MCHANISMS Augustus D, Willhauck, Melrose, Mass., assi'gnor to United Shoe-Machinery Corporation, Flemington, N. J., a corporation of New Jerseyr Y Application April 4, wsa-serial No. 280,468 l reclaim.; (pct. 895-24) This invention relates toguns and, moreparticularly, to improved breech operating mechanism andbreech controlled tiring mechanism for an lautomatic gun.

The illustrated gunis [adapted to receive ammunition from an improved ramming mechanism .which forms the subject-matter of an `application'of i Charles I; Gross, Serial No. 280,498, tiled on April 4, 1952,' to which the ammunition is supplied by a loading `mechanism form'- ing the subject-matter of another application, that of C. W. Greene, SerialV No. 280,524, filed"on`Apri1 4,1952.

In gunshaving the sliding wedge type of, breech mech'- anism, of which the present gun is an example, apart of the opening movement of the breechblock'is utilized to operate extractors to eject an empty shell case from the gun. This operation causes the operatingmechanis'm for the breechblock to be relatively heavily loaded at or near the end` of its breech openingfmovement. Again, at the beginning of the opening movement ofithefbreechblock, its operating mechanismis subjected to a relatively great load in overcoming the inertia of the breechtiring pressure invention, the illustrated breech mechanism comprises,l

with a crank shaft, a' pairof iiXed cams: which cooperate with the lcrank shaftdurin'grecoil r'novementofvLthe' "gun to impart an opening movement to th' breechblo'ckj'one of theicamsand the crankshaft being arranged effectively to impart a movement of 'overtravel to the Vbreechblock beyond its normal open position 'whihis utilized to operi ate the eXtractors t'oeject" the'emptyfshell case''from the gun. "'In the ap'plicationofthe present invention to the illustrated breechmechanis'm, one cam is arr'angedto cooperatefwith the' crank shafttofthe liestn advantage to initiate the opening movementiof 'thebreechblock 'How'- e'ver; ,asu this cam becomes "more'andfmorel ineffectual, on accoimt ofits Ichanging"relation't'o the i'eco'ilingV crank shaft, the Oth'er'eain" is designed "totak'e" over "theopera"-` tion. of the crank shaft Aat fthe "eud'of'the opening movementofthe breechblockf Y 'I f Hreto'fore; lbree'ch mechanism has* been designed' to have'a" locking 'ete'ct 'upon the breechblock whe'iifthelatter is" in' its closed positiofand ordinarily to thdetriment of 3 i-t`s effectiveness lin driving the breechblock `throughout its stroke. In the peseii'tconstrution, on the otherliand; the-breechoperating mechanism` is arrangedlwith regard to the best possible driving characteristics,1andis combine`clin accordance with 4f ,urther feature 'of the 4invention, 'with separate means`-for locking the breechblock in its closed position, this locking means being operated to vso constructed and -arranged as to insure the retraction.

Y 2 release thebreechblock in response to recoiling movement of thegun and inadvance Yof the timejwhen the breech operating mechanism is actuated to open the breechblock. Furthermore, upon being released from the breechlock the locking means is held in its inoperative position by the breechblock, which later .permits the locking means to move back into its locking position automatically upon the arrival of the breechblock in its closed position. Invention is also to be recognized in the combination with the locking means of ring mechanism, the control and operation of which is also related to the opening and closing'movements of. the breechblock, as well as to the movements of the gun in recoil and counter-recoil. More specifically, in addition to having the usual ring pin arrangedto slide from within the breechblock into engagement `with the primer of a shell, the illustrated tiring mechanismY comprises `connections associated with the labove-mentioned locking means kfor operating the ring pin automatically when the breechblock has become locked in its closed position. These connections are also of the tiring pin withinthe breechblock before its opening movement takes place.

These and other featuresof the invention will now be describedin Vdetail with reference to the accompanying drawings, and will be set forth in the claims. n

gun embodying the invention, together with a ramming mechanism and a part ofa hoist for supplying ammunition to' the gun; Y

. Fig. 2 is a side elevation of the gun and ramming mechanism shown in Fig. 1 as viewed from the left;

Fig. 3 is a Vside elevation of the breech mechanism of the gun as viewed from the right;

v Fig. 4 is a plan view of the breech mechanism when the gun is in battery; V

Fig.'5 is asectional plan view of the breech mechanism with the gun in battery; and v Figs. 6 and 7 are sectional plan views of the breech mechanism illustrating thebreechblock in its open position, Fig. 7 illustrating a shell being projected into the chamber of the gun by the ramming mechanism.

Each unit of the illustrated gun (the right-hand unit only being shown in the drawings) comprises a slide 10 in which atube 12 (Fig. l) is mounted for recoiling movement. `Each slide has a trunnion 16 at each side, rotatably mounted in'standards 18, V18 xed to the gun carriage, permitting the gun to be swung in elevation. Associated with each unit of the gun is ahoist '20 which -automaticallyvsupplies ammunition to a ramming mechanism 22 (oi:` the type disclosed in theAGross application referred to above), the latter being arranged to transfer the Arounds laterally of the gun from the hoist to the axis of the tube, and then to project the rounds into the chamber 24 (Fig. 7) of the tube axially thereof.

' The illustrated gun comprises a breech mechanism of the sliding wedge type, and has a breechV ring 26 (Figs. 5, 6` and 7), into which the tube is threaded, the ring having integral therewith opposed 'slides 2,8, 28 between which-1afbre'echblockl 30'is'mounted to reciprocate horizontally.:"Ltigs 31, 32 iixed tov the-*breech ring slide, when the'lgun recoils, in' guidewaysformed in plates 33, 34k respectively, which are iixed upon the slide it). Ex-

tractors-35 having lips 36 adapted to be engaged by closed position, shoulders 42 at the rear sides of the cam slots engage the lugs 38 and cause the extractors Vto rock upon the tube, and to eject the empty shell case from the gun. The breechblock is locked in its open position by the .engagement of another set Vof shoulders 44 (Figs. 4 and 7) at the forward sidesof the cam slots with the lugs 38.

The lugs are connected to .a buffer4 mechanismv cornprising levers 46, 46 ione of which is pivoted upon'.each of thefslides 28 and is connected atv itsupper end by a link 47 to the flug. The lower end "of each lever 46 is pivoted to a spring plunger 48,-.arranged to slide in an hydraulic buffer cylinder 49 of usual construction and fixed to the .breech ring. y

Opening and closing movements of the breechblock are caused and controlled by the following mechanism. A shaft 50, rotatably mounted in bearings 52 on the breech ring, has a central crank arm 54 (Figs. 3, 6 and 7) upon which aY block 56 ispivoted, the block being arranged to slide in a slot S8 formed in the breechblock. Pivoted at 59 upon the crank arm 54 is a yoke 60 to each side of which are fixed plungers 61 arranged to bear against cornpression springs (not shown) encased in tubes 62. A holder 64 for these tubes is carried by. rods 65 and struts v66 which are fixed to the bearings 52. The crank arm S4 is thus urged in a clockwise direction, Ytending always to drive thc breechblock toward its closed position.

As stated above, the breechblock is locked in its open position by the extractor lugs 38, but is released, whena round is inserted into the chamber, by the action of they round upon the lips 36 of the extractors which are rocked to movethe lugs off the shoulders 44 of the cam slots 40. Firing is effected automatically by a sliding ring pin 67 which impinges upon the primer of the shell.

Mechanism operated by the recoil of the gun isV provided for movingV the breechblock to its open position. This mechanism comprises a cam plate 68 fixedto the plate 33, and having a cam opening 69 into which extends a crank 70 fixed to the upper end of the shaft 50. When the gun recoils from its battery position (Fig. 4), the crank 70, since it moves with the breech ring, moves rearwardly with the gun, but is not rotated, at first, because it lruns along a straight portion,71 of' the cam opening. The opening of the breechblock is thus delayed to permit retraction of the tiring pin' 67 into the brecchblock, as will be described below. g Later, when the crank 70.1'noves` onto an incline 72, the shaft and crank arm 54 Vare rotated counterclockwise whereby the b'reechblock is moved away from its closed position against the pressure of the spring loaded plunger 6l. At this time, thev direction of the pressure between therinclinc and the crank-70 is approximately at a right angle to the arm of the crank'70, and an effectual drivng'relation exists between the cam and crank. However, near the end of the recoil movement, when the crank 76 reaches a shoulder 73 at the outer end of the incline, the direction of the pressure between the crank and the cam becomes so nearly. parallel to the arm of the crank that only a small component of the pressure between the crank and the cam is eiectual'to turn the crank, Before this latter condition can take place, another crank 76 on the lower endY ofthe shaft 50 cooperates with a second cam 78 in the plate 80 which is fixed to the plate 34 to operate the .crank shaft. That is, when the-crank 70 reaches the Shoulder 73 the crank76 will have been moved into contact with anincline 82 on the cam 80, the pressure between which and the crank 76 is directed nearly perpendicular'to the arm of the crank 76, whereby an effective drive for the crankshaft is established. From this Vpoint in the recoil movement of the gun until the end of such movement has been reached, the crank 70 moves freely within a clearance opening 83 in the plate 68 without engaging it, the crankshaft at this time being under the control of the crank 76 which bears against the outer side of a restricted "enraged, Y

' opening 84 in the cam 80. It is during the period when the crank 76 approaches and passes the inner end of the incline 82 that a movement of overtravel of the breechblock beyond its open position yis imparted to the breechblock, and the extractor lugs 38 are cammed forwardly of the gun Vby the shoulder-s 42 of the breechblock to impart a shell ejecting movement to the extractors.

After the crank 76 has fully entered the restricted opening 34 and the counter-recoil movement of ythe gun has begun, the crank engages a short incline S6 at the inner side of the opening 8-4.which, with the'opposite portion of the incline. 82, controls the reverse overtravel movement of the Vbreechblock until it is returned to its open position where it is Alocked by4 the engagement of 'its shoulders 44 with thepextractor lugs 38. The crank 76 now having passed off the inclirie86, it runs freely along a straight surface 87 of the cam 78, without being driven thereby, during the remainder of the counter-recoil movement of the gun back to its battery position. Y

Since the firing of the illustrated gun depends upon the operation of the ramming mechanism, this mechanism will now be briey described, but only so far as is necessary for an understanding of the operation of the breech mechanism. For a more complete description of the ramming mechanism reference may be made to the` above-mentioned Gross application. The rammer comprises one pair of arms 96, 96 (Fig. 2) and a second pair of arms 98,l 98 upon the outer ends of which is mounted a frame adapted to hold one shell. Immediately after a shell has been deposited into the frame from the hoist 20 these parts have the relation in which they are illustrated in Fig. l, the pairs of arms 96 ,98 extending lengthwise of the gun. A spring loaded plunger 101 arranged toslide in a housing 102 supplies the force for operating driving mechanism 103 for the arms 96, 98 which are swung in a counterclockwise direction to bring the remmer frame into such a'positionv (Fig. 7) that the round is coaxial with the gun. As the rammer frame'approachcs this position, a double chain 104,. having ngers 106 which grip the flange. of the shell, is operated to project the round into the chamber of the gun. lust before the shell is seated in the chamber the ange of the'shel engages theV lips 36 of the extractors which, under the control of the buffer mechanism associated therewith, decelerate the ramming movement of the shell from a velocity of about ,40 ft. per second to approximately l0 ft. per second. Before this movement of the extractors is completed the lugs 38 are moved from beneath the shoulders 44 on the breechblock permitting Vthe latter to be closed. When the;breechblock arrives at.its.closed position, it is automatically locked in this position and the shell is tired, as will be more fully described below.

When the gun recoils the plunger 101 is carried rearwardly vto its energized position Vby the lug 31, which abuts a collar 108 lfixed to the plunger, without having any effect upon therammer frame' because'of the use of one-way clutch mechanism between these parts, and the plungerris temporarily held in its energizedV position by a latch 110. The latch is pivoted at 112 on the base of the ramming mechanism and is arranged to overlie a shoulderf114formed upon the collar 108. vThis latch has an arm 116 to the end of which is connected the plunger of a solenoid 118, which, when it is energized by closing an electrical tiring-circuit (not shown),'re tracts the latchk from the shoulder 114'., iA cycle of. operation of the ramming mechanism is thus'started," the shelldtherein immediatelybeing swung away Yfrom-the hoist tothe axis ofthe gun, and then rammed into the gun` vWhenthe breechblockis closed the gun is automatically tired as will now be described., 'Y f Y The firing-pin 67 (Figs. 5, 6 and 7,) is mounted to slide in a bore 120 in the breechblock'from a retracted position within the block, as illustrated in Figs. 6 andr7, into its tiring position as illustrated in Fig. 5. #It is thus operated by a lever 122 to which the tiring pin is pivoted at 124, the lever being mounted to swing in a slot 126 in the breechblock about a pin 128 which is fixed to the block. In each side of the lever 122 there is an elongated slot 129, these slots being arranged'to receive a pair of pins 130, 130 which project toward each other from a bifurcated plunger 132V which is mounted to slide in the breech ring vlengthwise of the gun. The plunger 132 is pivoted at 134 to one arm 136 of a lever having two otherarms 138, 140, this lever being fixed Vto a 4shaft 142 which is rotatably mounted upon a bracket 144 xed to the breech ring.` A spring loaded plunger 146 is pivoted at 148 to the arm 138 and causes the tiring pinto `be urged toward `its firing position through the connections justidescribed.

When the breechblock is out of its closed position, the forward end of the plunger 132 abuts the rear surface of the breechblock, and the tiring pin is held in its retracted position. When the breechblock moves toward its closed position, the lever 122 at first slides freely with respect to, and without being moved by, the pins 130. However, when the breechblock arrives at its fully closed position, a socket 149 formed in the block at each side of the slot 126 becomes alinedwith the plunger 132 which then enters the socket, and causes the tiring pin to impinge upon the primer of the shell in the gun. 'Ihe gun is now tired and begins its recoil movement, but before any movement of the breechblock away from its closed position takes place, a crank pin 150 on the arm 140 engages a cam 152 which is flxed to the plate 80. The tiring pin is thus moved into its retracted position as shown in Fig. 6. The slots 129 in the lever 122 now being parallel to the path of the breechblock, its opening movement imparts no movement to the firing pin, and the tiring pin is held in its retracted position by engagement of the end of the plunger 132 with the rear surface of the breechblock `throughout the remainder of the tiring cycle until immediately beforeV the gun is next red. 1

The tiring cycle of the `gun and the operation ofthe Vbreech mechanism will now be` summarized. When at rest, the gun is in battery with-the breech open as illustrated in Fig. 7. When thev next round of ammunition is delivered into the gum chamber by the ramming mechanism, the extractors'are engaged'by the lflange 37 on the shell case and are swung so as lto move the lugs 38 away from the shoulders 44 of the breechblock, whereby the latter is permitted to slide into its closed position under the inuence of the spring loaded operating shaft 50. This swinging movement of the extractors is snubbed by the buffer mechanism associated with them, in order to avoid excessive jolting of the shell as it becomes seated in the chamber of the gun. While the breechblock slides toward its closed position the pins 130 slide freely within the slots 129 in the lever 122 without operating it, and the 'firing pin 67 is held in its retracted position by the plunger 132 the forward end of which engages the breechblock. However, when the breechblock reaches its closed position, the plunger 1-32 slides into the socket 149 causing the breechblock to be locked in its closed position, the lever 122 to be swung forwardly,

and the firing pin to be operated to fire the shell.

Upon being tired, the gun immediately recoilsl bring- ,ing the crank pin 150 into engagement with the cam 152,

whereby the tiring pin is again retracted within the breechblock. Later, the crank 70 moves onto the incline 72 of the cam plate 68 causing the breechblock to be moved to its open position. During the iinal portion of therecoil movement the crank 76 cooperates with the cam plate 80 to impart a movement of overtravel to the breechblock which is utilized to operate the extractors 35 to eject the empty shell case from the gun.

This movement of overtravel is reversed during, and in predetermined relation to, the initial counter-recoil movement of the gun. Upon being returned to its open position, the breechblock is locked therein by the erigagement of its shoulders 44 with the extractor lugs 38, but the gun returns to battery with a continuous counterrecoil movement, the breech remaining open until the next shell tobe lired is rammed into thel gun. p

Having'thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

l. In a breech mechanism for a gun having a breechblock mounted to slide between open and closed, positions, operating mechanism for said lbreechblock comprising a crank shaft movable with the gun in recoil and counter-recoil, said shafthaving a pair of angularly related crank arms, and a pair of xed cams, one of said cams being constructed and arranged to cooperate with one of said crank arms during recoil movement of the gun to impart an opening movement to said breechblock, theA other of said cams being constructed and arranged to cooperate with the other of said crank arms during the terminal portion of the recoil movement of the gun and during its initial counter-recoil movement positively to impart a movement of overtravel to said breechblock beyond and back to its open position.

2. In a breech mechanism for a gun having a slide in which a gun tube is mounted for recoil and counterrecoil movements, a breechblock associated with said tube and mounted to slide between open and closed positions, operating mechanism for said breechblock comprising a crank shaft mounted for movement with said tube, said shaft having a pair of angularly related crank arms, and a pair of cams fixed to said slide, each of said cams being associated with one of said crank arms, said cams being constructed and arranged to cooperate successively Vwith said crank arms during recoil movement of the gun to move said breechblock into and beyond its open position and to return said breechblock to its open position during the initial counter-recoil movement of the gun tube.

3. In a breech mechanism for a gun having a slide in which a gun tube is mounted for recoil and counterrecoil movements, a breechblock associated with said tube and mounted to slide between open and closed po- ,sitions, operating mechanism for said breechblock comprising a crank shaft operatively connected to said breechblock `and mounted for movement with said tube, said shaft having a pair of angularly related cranks, and a pair of cams xed to said slide, one cam being associated with each of said cranks, said cams being shaped so Vas to permit said breechblock to move freely between its said positions when said gun tube is in battery, one of said cams being constructed and arranged to cooperate with one of said cranks during the recoil movement of the gun to impart an opening movement to said breechblock, the other cam being constructed and arranged to cooperate with the other crank to impart a movement of overtravel to said breechblock beyond and then back to its open position during the terminal portion of the recoil movement and the initial counter-recoil movement of the gun, respectively.

4. In a breech mechanism for a gun having a breechblock mounted to slide between open and closed positions, operating mechanism for said breechblock comprising a crank shaft operatively connected to said breechblock and movable with the gun in recoil and counterrecoil, said crank shafthaving a pair of angularly related cranks, yielding means actingupon saidcrank shaft to urge said breechblocktoward its closed position, and

Va pair of fixed cams, one cam being associated with each of said cranks, one cam and the crank associated therewith being constructed and arranged toimpart an openblock mounted to slide into and out of a closed position, mechanism for operating said breechblock comprising a cam and Va shaft which is movable with the gun in recoil and counter-recoil and has a crank cooperating with said cam to move said breechblock into its open position in-response to recoil movement of the gun, the ,combination of a second cam and a second crank on said shaft, said second cam and crank cooperating to impart a movement of overtravel to said breeclfrblock,A beyond and back to its open position during the terminal portion of the recoil movement of the gun and its initial counter-recoil movement respectively, extractors, and connections between said extractors and said breechblock actuated by said breechblock during its movement of overtravel for operating said extractors to eject a shell from the gun. l c

6. In 'a breech mechanism for a gun having aY breechblock mounted to siide into and out of a closed position, operating mechanism for said breechblock comprising a shaft movable with the gun in recoil and countercoil, said operating mechanism also comprising a xed cam andV a crank fixed to said shaft, said crank being operated by said cam in response to recoil movement of the gun to cause said breechblock to be moved into its open position, the combination of a second cam, a second crank fixed to said shaft and arranged to cooperate with said second cam to impart a movement of overtravel to said breechblock beyond its open position, extractors for ejecting a shell from the gun, and extractor cam surfaces upon said breechblock arranged to opcrate said extractors to eject the shell during the said movement of overtravel of said breechblock, said second cam and crank also being arranged to reverse the said movement of overtravel of said breechblock during the initial counter-recoil movement of the gun.

7. In a breech mechanism for a gun, a breechblock mounted for movement between open and closed positions, a tiring pin mounted upon said breechblock for movement from within the breechblock into tiring position, and mechanism for operating said firing pin comprising a spring loaded plunger cooperating with a shoulder on said breechblock to hold said firing pin retracted Within said breechblock while said breechblock is outof its closed position, said plunger also being mounted for movement across said shoulder upon the arrival of said breechblock in its closed position whereby said tiring pin isreleased for movement into its firing position. i Y, 8. In 'a breech mechanism for a gun having a breechblock mounted for movement between open and closed positions, said breechblock carrying a tiring pin mounted for movement from within it into a tiring-position, mechanism forV operating said firing pin comprising a locking member biased toward said breechblock into engagement therewith to hold said firing pin retracted within said breechblock while it is out of its closed position, said breechblock havingV a shoulder across which said memberY is moved u pon the arrival of `said breechblock in its closed Vposition whereby said breechblock is locked intitrs closed positiony and said tiring pin is released for movement into its firing-position in succession.

9. In a breech mechanism for va gun having a breechblock mounted to move between open and closedxpositions, a tiring pin mounted upon said breechblock for movement between a retracted position within said breechblock and a tiring position, mechanism for operating said firing pin c'oniprisingV a locking member mounted for movementV transversely of the path of said breechblock into yielding engagement `therewith whereby said fringxpin is retracted within said breechblock when it is 'away from its closed position,`said breechblock having a socket for receiving said member when said breechblock is in its closed position whereby it is simultaneous- 1y locked in its closedl position and said tiring pin is released for movement into its firing position.

10. In a breech mechanism for a gun having a breech ring in which a breechblock is arranged to slide between an open and a closed position, a 'ring pin mounted upon said breechblock to slide from within said breechblock into a tiring position in which it projects out of said breechblock, yand means for operating said tiring pin comprising a spring loaded plunger mounted to slide in the breech ring across the path of said breechblock into yieldingv engagement therewith, pin and slot connections between saidfplunger and said tiring pin, said breechblock having a socket for receiving said plunger upon the arrival of said breechblock into its closed position, whereby it isrsimultaneously locked in its closed position and said firing pin is released for movement into its tiring position.

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